Why You Need Carbs to Build Strength and Size

Good nutrition is essential for all, especially for athletes in training. Regardless of your sport, a good diet fuels your muscles for physical activity, helps you achieve optimal performance and even prevents injury. In contrast, not taking in enough food (or the right kind of food at the right times) can lead to less than optimal health and inadequate energy reserves.

Good nutrition is essential for all, especially for athletes in training. Regardless of your sport, a good diet fuels your muscles for physical activity, helps you achieve optimal performance and even prevents injury. In contrast, not taking in enough food (or the right kind of food at the right times) can lead to less than optimal health and inadequate energy reserves.

A major source of our energy comes from food containing carbohydrates. Carbs are important for different forms of exercise, and they are especially important during high intensity workouts and during competition. When you take in carbs, your body converts them into a form of sugar called glucose that can be used for energy. The glucose, in turn, is changed to glycogen so that it can be easily stored in your muscles and liver for later use. It is the predominant storage form of glucose and carbohydrates in humans, and it's an essential fuel source for the body during all forms of exercise.

Unfortunately, in recent years we have seen numerous recommendations against carbs. In fact, it's been suggested that high-protein, high-fat and even carbohydrate restriction diets can improve athletic performance. Despite the plethora of new diet recommendations, much of this information lacks substantial scientific evidence.

On the other hand, more than 50 years of scientific evidence has overwhelmingly shown that a good carbohydrate diet is crucial to maintaining and improving athletic performance. In fact, multiple studies show that fatigue and lower performance are associated with low carbohydrate diets that cause glycogen depletion. Studies also show that low levels may cause overtraining.

These findings are regularly confirmed by real-life experiences of elite athletes. For instance, Kenyan runners have dominated international marathon events for decades, and they are regarded as the best endurance runners in history. The percentage of carbohydrates in their diet is 76.5 percent, and 20 percent of their total daily caloric intake comes from sugar. This kind of anecdotal evidence, combined with athletes and sports teams looking for a competitive advantage, has led to an increasing amount of research in this area, and the emergence of the still developing field of sports nutrition.

In March 2016, an international Position Stand on Nutrition and Sports Performance laid out the most comprehensive guidelines to date on "nutrition factors that have been determined to influence athletic performance and emerging trends in the field of sports nutrition." This paper made it overwhelmingly clear that when you eat is just as important as what you eat.

The message here is to be strategic with your sports nutrition and follow scientific guidelines to maximize your performance before, during and after competition or training. The converse is also true: by excluding carbs, you will put yourself at a competitive disadvantage.

Here are three occasions when you have the opportunity maximize your energy reserves:

Before Exercise

Ten to 15 minutes before your workout, take 8-12 oz of a carbohydrate/protein drink (3:1 ratio of carbs to protein). This will provide immediate fuel for exercise without using up your muscle glycogen stores. Make sure you are also well hydrated!

During Exercise

For activity longer than an hour, take small sips of a carbohydrate/protein drink every 20 minutes. This will spare your muscle glycogen and delay fatigue. If you typically have an easy workout or just like to go out for an light jog, you don't need this strategy.

After Exercise

Start refueling your muscles very early! Your muscles store twice the amount of glycogen when carbs/protein supplements are taken immediately after exercise, compared to two hours afterward. Start refueling before you start your shower.

Finally, keep learning: Read food labels or talk to a sports nutritionist—or do both. You can still eat that pasta, but pay attention to these three proven strategies for maximizing your muscles' fuel. FYI, there is a range of commercially available drinks and sports products that can provide easily digestible carbs. You can add protein powder to make up the optimal 3:1 ratio.

Wayne Phillips
- Wayne Phillips, Ph.D., FACSM, is the chief science officer at MuscleSound, a company that tracks glycogen and muscle composition using ultrasound technology in order to maximize athletic performance. Dr. Phillips holds a Master of Science in physical education and sports science from Loughborough Un
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